Automotive transmission control system and mechanism



Aug. 14, 1956 I G. T. RANDOL 2,758,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND. MECHANISM 17 Sheets-Sheet 1 Original Fil ed Aug. 3. 1948 www wk Q hum M.

ATTORNEYS.

// INVENTOR Glenn 7? Randal, BY z/meu; fizc m Aug. 14, 1956 G. T. RANDOL 5 AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM 17 Sheets-Sheet 5 Original Filed Aug. 3, 1948 INVENTOR Glenn 7. Randal,

ATTORNEYS.

Aug. 14, 1956 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. 5, 1948 17 Sheets-Sheet 4 INVENTOR: Glenn 7? Randal,

A TTOR NEYS.

Aug. 14, 1956 .G. T. RANDOL 2,753,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Au s, 1948 V 17 Sheets-Sheet 5 INVENTOR: Glenn 7. Randal,

Q ATTORNEYS.

Aug. 14, 1956 G. T. RANDOL I AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM 17 Shets-Sheet 6 Original Filed Aug. '3, 1948 INVENTOR.

Glenn 7T Randal,

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Aug. 14, 1956 s. T. RANDOL 2,753,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. s, 1948 17 Sheets-Sheet 7 E w wfl brake roor and 511/: year e/ a m Sun year 30/73 3 [forum/"02 511/: year brake r060)- fia'rec Jra'I e cluc'cfi en ayes. Brake rota/- oke/ y from sun year flz'rec drive civic/z enyayea. Brake ml dalsezgzq fro/r1 5w? year 01-666 year 5w: year iokyE/rekerseai 5w: year firake 2050/ v INVENTOR: Glenn 7? Randal,

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17 Sheets-Sheet 8 Aug. 14, 1956 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. :5, 194a .Aug. 14, 1956 G. T. RANDOL 2,758,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. 3, 1948 17 Sheets-Sheet 9 BE E INVENTOR:

Glenn 7. Randal,

ATTORNEYS.

Aug. 14, 1956 RANDQL 2,758,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. 3, 1948 17 Shets-Sheet 1O a0 325 424 '2 [2% 260 42 w zz 9 2M 4a A TTORN E YS Aug. 14, 1956 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM 1'7 Sheets-Sheet 11 Original Filed Aug. 3, 1948 INVENTOR: Glenn '7. Randal,

AT ORNEYS.

Aug. 14, 1956 G T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM l7 Sheets-Sheet 12 Original Filed Aug. 3, 1948 G/ehh T. Randal,

2Dzce AT- ORNEYS. v

' Aug.14,1956 1 GTLRANQO'L 2,758,683v

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM .Ofiginal Filed Aug. 5, 1948 v 1'7 Sheets-Sheet 1s INVENTOR: Glenn 7? Randal,

- ATTORNEYS.

Aug. 14, 1956 i G.YT.RANDOL 2,758,683

' AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Original Filed Aug. 3, 1948 1'7 Sh'ee'ts-Sheet 14 A INVENTOR: "Glenn I'Rqndol,

IIIAITTORNEYS.

Aug. 14, 1956 I 6. TQRANDOL 2 8,6 3

AUTOMOTIVE TRANSMISSIQN CONTROL SYSTEM AND MECHANISM I Original Filed Aug. 5, 1948 17 Sheets$heet. 15

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INVENTOR:

Glenn T. Randal,

ATTORNEYS.

-Aug. 14, 1956 2,758,683

AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM G. 'r. RA-NDQL I l7 Sheets-Sheet 16 Original Filed Aug. 3, 1948 INVENTOR I Glenn 7'. Rand0/, M 9 2M ATTORNEYS.

Aug. 14, 1956 G. T. RANDOL AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM 17 Sheets-Sheet 17 Original Filed Aug. 3, 1948 QNMN Ea BY xmza, q ATTORNEYS.

United States Patent AUTOMOTIVE TRANSMISSION CONTROL SYSTEM AND MECHANISM Glenn T. Randol, Mountain Lake Park, Md.

92 '(Ilailns. (Cl. 192-'-.048)

The present invention relates to control systems for change-speed gearing, and'particularly to improvements relating to the control of transmission devices for motor vehicles. This application is a continuation of my prior co-pending application Serial No. 42,174, filed August 3', 1948, for Automotive Transmission Control, now abandoned. I

The invention finds particular utility in connection with automotive transmission systems having at least two distinct torque ratios or drives, where the shifting between such ratios is induced by power means and/or centrifugal force or the like, but wherein the driver is afiorded supervisory control over the action of the shifting means. Such transmissions are sometimes referred to as semiautomatic transmissions, as distinguished from fully automatic transmissions wherein ratio changing is not under the direct control of the driver. The present invention aims to provide improved means whereby the actionof a self-shifting transmission system may be definitely and accurately controlled by the driver without the use of any special or nonstandard control devices and, in fact, with the use of no control devices other than the conventional control elements such as the gear shift lever and clutch pedal, and/or accelerator pedal mechanism, commonly provided upon motor vehicles having manually-shifted transmissions. In accelerating a vehicle equipped with my improved system, a lower speed (higher torque) gear ratio may be maintained as long as the driver desires, and shifting only occurs at the electionof the driver response, for example, to momentary release of the accelerator pedal. Such transmissions have the advantage that no compromises are necessary in the selection of speeds or speed ranges at which shifting will occur, and the driver may demand and secure maximum car performance if he desires, whereas with fully automatic tra'nsmissionscompromises must be made in the selection of ratio changing speeds, due to such consideration as engine noise, with resultant sacrifice of maximum car performance. It is an important object of the present invention to provide a control system for a transmission of the indicated character which provides effective driver supervision of the self-shifting action without requiring the driver, in order to exercise such supervision, to actuate :any special or unorthodox controlling agencies whatever, or to move the standard control devices in any unnatural or unusual manner. Thus, as indicated, a vehicle equipped with my improved system may incorporate a conventional accelerator pedal and a conventional hand-shift lever with their respective mechanical linkage, mounted, for example, on the steering column and movable in a standard orconventional pattern, and the improved controlling system of my present invention is so interrelated with these standard control elements that the automatic shifting action may be controlled or supervised without the necessity for any unusual movements of such standard controls and without the manipulation of any other control means whatever. An advantage of my invention, therefore, is that in an emergency, when the driver may not have time to think 2,758,683 Patented Aug. 14, 1956 'ice or to reach for a special control, his already-learned reactions (which with an experienced driver result in quick and spontaneous actuation of the standardized controls) will cause my improved system to function in a safe and proper manner.

It is also an object of this invention to provide a control system of the indicated character wherein a high speed, low torque range may in effect be locked out whenever desired, in a very simple manner, without requiring the manipulation of special controlling agencies such as the special lock-out cables or lock-out shifting means commonly employed in conjunction with automatic overdrive units and semi-automatic transmissions, and automatic transmissions as frequently constructed. In the latter connection, it will be recognized that the principles of the invention are also useful in connection with fully automatic transmissions where a manual control has been considered necessary to engage and disengage an emergency low range, or to select between two driving ranges.

Still another object of this invention is to provide an improved control system of the indicated character which is simple, reliable, inexpensive, easily installed, and the principal components of which are readily accessible and replaceable if such servicing should become necessary.

A still further and important object of the present invention is the provision of novel conditioning means actuated by the engine accelerator mechanism for controlling the effectiveness of diiferential fluid pressures for operating the transmission servo-mechanism whereby operation of the accelerator mechanism from engine idling position is effective to enable such pressure difie rential conditions to energize the servo-mechanism at reduced etiectiveness insuthcient to operate the servo-mechanism to change the effective drive ratio of the transmission, while release of the accelerator mechanism back. to idling position causes maximum pressure difierential conditions sufiicicnt to operate the servo-mechanism without additional operation of said means being required.

;A more specific object related to the last stated object.

above is the provision in such novel conditioning means of a switch device controllable by the accelerator mechanism for causing two-stage energization of the servomechanism responsive to depressing and release of the driving ranges be selectivelyv employed whenever the driver wishes, but the transmission drive-mechanism may.

be so constructed as to provide either a free-wheeling or a positive two-way underdrive, which latter drive affords engine braking while operating the vehicle in overdrive range, in accordance with the drivers wishes or the driving condition encountered; while in addition, a forced or automatic downshift to such lower drive is eflected in response to a predetermined depressing movement of the accelerator pedal means or a governor device responsive to reduction in vehicular speed to a certain factor, respectively.

A more specific object of the invention is to provide improved controlling means for automatic or semiautomatic overdrive units including, without limitation thereto, overdrive units of the general type disclosed in Taylor Patent No. 2,398,814 granted April 23, 1946.

The invention consists of the novel constructions, arrangernents and devices to be hereinafter described and claimed for carrying out the foregoing general statement of the nature of my invention, and such other objectives, features, and advantages as will appear in lieu of presenting them categorically in the above statement, from the following detailed description considered in conjunction with certain preferred embodiments illustrated in the accompanying drawings, wherein:

Figure 1 is a partially diagrammatic side elevational view of an overdrive unit and control system components therefor incorporating the principles of the present invention, showing adjacent and interrelated parts of a motor vehicle in which the installation is incorporated, par-ts being broken away, and shown in high gear (direct drive) condition with the engine clutch fully engaged, the vehi'cle operating at an engine idling speed (accelerator pedal released), and wherein the electrical control circuits are depicted in solid lines to indicate energized condition thereof.

Figs. 2, 3 and 4 are horizontal sectional views of the overdrive reaction brake locking mechanism, taken substantially on the line 22 of Fig. 1 and looking in the direction of the arrows, the parts being shown in various operative positions and on a larger scale than in Fig. 1;

Fig. 5 is a vertical longitudinal sectional view taken axially through the overdrive unit and wherein the rotor brake bar is disengaged and the shiftable lock-out clutch collar in direct-drive position as shown in Fig. 1

Figs. 6 and 7 are cross-sectional views taken substantially on the lines 6-6 and 7-7 respectively of Fig. 5 and looking in the direction of the arrows;

Fig. 8 is a cross-sectional view similar to Fig. 7 but showing the rotor brake bar engaged, a condition eifective upon release of the accelerator pedal substantially at or above a predetermined vehicle speed while the lock-out clutch 'collar is in overdrive position;

Fig. 9 is a cross-sectional view taken on the line 9-9 of Fig. 5 "showing details of the torsional spring anchor plate;

Fig. 10 is a sectional elevational detailed view showing a floating member of a free wheeling clutch employed in the overdrive unit;

Figs. 11 and 12 are sectional views taken substantially on the lines 11-11 and 1212 respectively of Fig. 5 and looking in the direction of the arrows;

Fig. 13 is 'a fragmentary developed plan view taken substantially as indicated by the arrow 13 of Fig. 5;

Figs. .14, 15,16 and 17 are diagrammatic sectional'views of the planetary gearing and related lock mechanism for the reaction gear of the gearing, progressively indicating the functioning of thegearing components during the transmission of drives of different ratios;

Fig. 18 is a side elevational view of the overdrive unit showing in vertical section the principal parts of the toothed-escapement shifting mechanism;

Fig. 19 is a view'similar to Fig. 18 in a smaller scale and showingthe positions assumed by the parts during medial spring movement of the servomotor piston, wherein the rotor brake bar release has been efiected prior to a .s'hift of the clutch collar to lock-out direct drive position;

Fig. 20 is a diagrammatic perspective view of the gear shifting hand lever and adjacent parts;

Fig. 21 is a fragmentary plan view, with a part of the cover broken away, of the underdrive transmission mechanism .shown in .high gear established condition;

Fig. 22 is an enlarged view taken substantially on the line 22- 22 of Fig. 21, looking in the direction of the arrows and showing details of the shifting forks and associated interlocking mechanism carried on the interiorof the transmission cover;

Fig. 2-3 is an enlarged plan view taken substantially.

switch mechanism mounted at the lower end of the shifter control shaft;

Fig. 24 is an elevational view taken at right angles to Fig. 23;

Figs. 25 and 26 are sectional views taken substantially on the lines 25-25 and 2626 respectively of Fig. 24 and looking in the direction of the arrows;

Fig. 27 is a sectional view taken substantially on the line 2727 of Fig. 23 and looking in the direction of the arrows;

Fig. 28 is .a vertical sectional view of an electric conditioning switch and adjacent parts of its operating mechanism, with some components shown in elevation;

Fig. 29 is a view similar to Fig. 28 showing the switch parts in another position assumed during operation;

Figs. 30 and 31 are sectional views taken substantially on the lines 3t)30 and 31--31 respectively of Fig. 28 and looking in the direction of the arrows;

Figs. 32, 33, 34 and 35 are diagrammatic views similar to Fig. l, but with certain components omitted and showing parts of the controlling mechanism in different positions they occupy during operation, and wherein the electrical control circuits are depicted in solid and dashed lines to indicate respectively energized and non-energized conditions thereof;

Fig. 1A is a partly diagrammatic side elevational view generally similar to Fig. 1 but showing a modified arrangement; I

Fig. 1B is a similar view showing another modified arrangement, and wherein the electrical control circuits are depicted in dashed lines to indicate non-energized condition thereof;

'Fig. 2B is a partly diagrammatic elevational view similar 'to Fig. 20, showing a gear shifting hand lever suitable for use with the embodiment of Fig. 1B and indicating the shifting pattern thereof;

Fig; 3B is an enlarged plan view partly broken away, taken substantially from the line 3B-3B of Fig. 1B and looking in the direction of the arrows;

Fig. 4B 'is a view similar to Fig. 3B but with additional parts broken away and shown in section and with some of the parts in different position;

Figs. 5B and 6B are sectional views taken substantially onthe lines 5B5B and 6B-6B, respectively, of Fig. 3B and looking in the direction of the arrows;

Fig. '1C is a view similar to Fig. 1 showing another modification;

Fig. 2Cis an elevational view corresponding to Fig. 20, showing theshifting pattern of thehand lever incorporated in .the'embodiment of Fig. 1C, and wherein the electrical control circuits are depicted in dashed lines to indicate non-energized condition thereof;

Fig. 3Cis a plan view, with parts broken away and shown .in section, of gearing incorporated in the embodiment'of Fig. 1C;

Fig. 4C is a'fragmentary sectional elevational view taken substantially as indicated by the line 4C-4C of Fig..3C, and looking in the direction of the arrows;

Fig. SC is an enlarged sectional elevational view of a conditioning switch of the control mechanism incorporated in the embodiment of Fig. 1C;

Fig. 6C is a view similar to Fig. 5C of a part of the mechanism shown in the last-mentioned view, with the parts in difierent positions which they assume during operation; v

Fig. 7C is an enlarged sectional view of a supplemental switching device incorporated in the embodiment of Fig. 1C and forming part of the control mechanism shown in Figs. and 6C;

Fig. 8C 'is a sectional elevational view of a speed responsive governor and associated electrical switching means;

Fig. 9C is a cross-sectional view taken substantially on the line 9'C--9C of Fig. 8C;

"FigflO'C is a sectional elevational view of the driving means for, the speed governor, taken on the line 10C- 10C of Fig. 1C;

Fig. 1D is a view similar to Fig. 1 showing another modification and wherein the electrical control circuits are depicted in solid and dashed lines to indicate respectively energized and non-energized conditions thereof;

Fig. 2D is a plan view partly broken away showing gearing incorporated in the embodiment of Fig. 1D and other associated elements;

Fig. 3D is an enlarged interior view taken substantially on the line 3D-3D of Fig. 2D, of the gearing cover assembly, showing details of the two shifter forks and position-holding detent mechanism therefor;

Fig. 4D is a sectional view taken substantially on the line 4D-4D of Fig. 1D and looking in the direction of the arrows;

Fig. 5D is an enlarged sectional view taken substantially on the line 5D-5D of Fig. 1D and looking in the direction of the arrows;

Fig. 6D is an enlarged elevational view, partly broken away, of a conditioning switch construction employed in the embodiment of Fig. 113;

Fig. 7D is a view similar to Fig. 6D showing the parts in different positions assumed during operation; and

Fig. 8D is a perspective view of portions of a switch actuating structure incorporated in the embodiment of Fig. 1D.

Control system mechanism associated with an overdrive unit (Figures 1-35) The overdrive unit shown in Figs. 2-17 inclusive substantially corresponds to the construction disclosed in Taylor Patent No. 2,398,814 above referred to, and reference may be had to that patent for consideration of the details of construction and operation of such overdrive unit, which in and of itself forms no part of my present invention, apart from the manner in which it is interrelated with components of-the control system presently to be described. This unit may also be properly termed in a broader patent sense, a supplemental transmission ratio drive means, or a two-speed power transmission or drive as the claim language may require.

The overdrive unit employs a planetary gearing, and the overdrive ratio is effective whenever the sun gear 22 of the planet system is held stationary by reaction braking mechanism.

The overdrive unit is incorporated in a housing having a body portion 2 and end plate 3 secured together by screws 4. The housing is preferably interposed in torque tube 6 of an automobile behind the regular transmission 7, with sections of the tube engaged by necks 8 and 9 on the housing body and end plate respectively. Leading portion 11 of the propeller shaft provides the drive shaft of my unit, and trailing portion 12 forms the driven shaft. When power is being transmitted through the unit from drive shaft 11 to driven shaft 12, the mechanism is subjected to a certain kind of loading which I shall refer to as a driving load; and when the rear wheels of the car tend to overrun the rate at which they are driven, the mechanism is subjected to a different loading which I term coasting load; these terms being conventional in the trade.

As shown in Fig. 5, the overdrive transmission chosen for purposes of illustration comprises a planetary gearing having a. planet pinion 13 journaled on shaft 14 mounted on a pinion carrier 16 splined to drive shaft 11. Orbit ring gear 17 of the planetary system is mounted for rotation with driven shaft 12 by a hub 18 splined to the shaft and provided with a flange 19 peripherally splined to the orbit gear and held by retaining ring 21. Sun gear 22 is formed as part of a sleeve 23 freely journaled on the drive shaft on a bearing 24.

The entire mechanism is journaled in the housing by two main bearings 26 and 27. One of these is disposed about the drive shaft and is retained by end plate 3,

'While the other is interposed between hub 18 and neck 8 of the main housing. Hub 18 also carries speedometer gear 28; and an oil retaining ring 29 is interposed between the hub and neck behind gear 28.

Means are provided for holding the sun gear against rotation to effect planetary'operation of the system for establishing an overdrive connection between the shafts. For this purpose, a brake mechanism generally indicated by reference numeral 31 is employed; the brake being engaged by reverse (counterclockwise) torque of the sun gear under coasting load, and disengaged by forward (clockwise) torque of the sun gear under driving load. In the present specification, the references to direction of rotation and torque'(clockwise and counterclockwise) are taken as viewed from the left in Fig. 5; the clockwise rotation being considered-as forward in the conventional manner.

Brake 31 for establishing the overdrive connection comprises a peripherally toothed rotor 32 splined to a hub 33 connectable to sun gear sleeve 23 through a shiftable clutch member 34. Hub 33 is freely journaled on drive shaft 11 by bearing 36 and is restrained axially by retaining ring 37 and spacer bearings 38. By this arrangemenuthe brake rotor 32 is connected with the sun gear whenever clutch member 34 is in the dashed line position shown in Fig. 5 with its teeth 39 engaging teeth 41 and 42 respectively of the sleeve and hub.

Referring to Fig. 6, the overdrive brake further comprises a bar 43 disposed transversely of and oflfset from the rotor axis and axially slidable in a tubular casing 44 secured to the housing by screws 46. Brake bar 43 has a forward end 47 shaped to fit in the V-shaped notches formed between teeth 48 on rotor 32. In its extended position, the brake bar engages the toothed rotor as shown in dotted line position in Fig. 6; and in its retracted position the bar is disengaged from the rotor as illustrated in Fig. 7. It is apparent that the brake bar is disengageable by axial thrust applied on it by rotor 32 when the latter tends to turn clockwise'under torque imposed by the sun gear when the unit is subjected to driving load.,

Means are therefore provided for locking the brake bar against disengagement to maintain the overdrive connection. When the brake is locked up, the sun gear is thus held against clockwise rotation, and the driving thrust is transmitted by drive shaft 11 to orbit gear 17 through planet pinion 13 which, in turn, planetates about the fixed sun gear. The orbit gear thus rotates forwardly at a faster rate than the drive shaft, and this is reflected by increased speed of driven shaft 12 in accordance with the usual planetary overdrive principle.

As illustrated in Figs. 2 and 6, the locking means comprises a plunger 51 slidable within a transverse neck portion 52 of casing 44. When the plunger is extended, it lies between a pair of rollers 53 interposed between the end of brake bar 43 and a fixed reactor element or plug 54 threaded in the end 'of casing 44. In other words, when plunger 51 is inserted between the rollers, the overdrive brake is locked against disengagement. The locking plunger is normally urged toward extended position by a spring 56 interposed between the plunger and the outer end wall 57 of neck 52.

Means associated with a throttle pedal 58 (Fig. l) is provided for retracting lock plunger 51 to accommodate disengagement of the overdrive brake. A pull wire 59 attached to the plunger is carried forward in a protective sheath 61 secured at its rear end to cap 57 by a clamp 62 and terminating under and forwardly of the drivers compartment where'the wire is' provided with a stop 64 engageable by an eye 274 pivotally carried by an arm 272 of a star lever 266 actuatable by the throttle actuator or accelerator pedal through the agency of a link 67 which connects the pedal to another arm 66 of the star lever. Stop 64 is normally spaced ahead of eye 274 so wire 59 is pulled to start retraction of plunger 51 at the end of the throttle stroke when pedal 58 is fully depressed. Rollers 53 permit the plunger to be pulled 

